Machine for disintegration of cellulose pulp sheets

ABSTRACT

A machine for disintegration of cellulose pulp sheet which comprises an essentially vertical magazine to receive pulp sheet bales with the sheets preferably lying horizontally, said magazine having a bottom consisting of a bed of slightly spaced, mutually parallel tearing tooth rods which are longitudinally relatively movable to one another and may include two groups which are alternately movable in opposite directions.

United States Patent 1 Hessner et al.

MACHINE FOR DISINTEGRATION OF CELLULOSE PULP SHEETS Inventors: HansHessner, Djursholm; Per Olof Nilsson, l-lallsberg, both of SwedenAssignee: Aktiebolaget Stille-Werner,

Stockholm, Sweden Filed: Feb. 24, 1971 App1.No.: 118,460

Foreign Application Priority Data Feb. 24, 1970 Sweden ..2362/70 [1.8.CL ..24l/94, 241/263 Int. Cl .l ..B02 1/12 Field of Search ..24l/28, 94,262, 263,283; 144/189; 146/149, 150 R 1451 Jan. 9, 1973 [56] ReferencesCited UNITED STATES PATENTS 2,342,213 2/1944 Ostrander .241 /94 208,89010/1878 Cornell et a1... .241/28 868,617 10/1907 Scozzari ..241/283 x3,502,275 3/1970 Watson .241 94 x Primary Examiner-Granville Y. Custer,Jr. Attorney-Martin Kirkpatrick [57] ABSTRACT A machine fordisintegration of cellulose pulp sheet which comprises an essentiallyvertical magazine to receive pulp sheet bales with the sheets preferablylying horizontally, said magazine having a bottom consisting of a bed ofslightly spaced, mutually parallel tearing tooth rods which arelongitudinally relatively movable to one another and may include twogroups which are alternately movable in opposite directions.

8 Claims, 2 Drawing Figures PATENTEUJAN 9 I973 3 709' SHEET 1 UF 2PATENTEDJAN 9|975 3 709441 SHEET 2 BF 2 MACHINE FOR DISINTEGRATION OFCELLULOSE PULP SHEETS For disintegration of cellulose pulp in sheetswhich are normally delivered from the mills in big bales one hasheretofore as far as known essentially relied upon a softening of thenormally very hard pulp sheets in water in connection with thedisintegration. This has not caused any problems because one has in anycase been working with the pulp in a water suspension of a rather lowconcentration in the succeeding steps of the process in question, suchas at paper making. However, with the increased use of cellulose asfluff, i.e., a dry defibrated pulp wherein the fibers are comparativelywell separated from each other, it has been necessary to developdisintegrating or defibrating means of a sufficient capacity andreliability; at the same time it has been found necessary to ensure thatthe disintegration or defibration is not carried on too far, so that agreat proportion of the pulp is converted into something which might betermed short staple cellulose dust.

One known device for the disintegration of cellulose pulp is the socalled hammer mill which, however, has the inherent disadvantage as faras the raw material is concerned that it is limited to work with pulpwebs on rolls. However, as cellulose pulp is commonly delivered insheets, packed in bales, attempts have been made to come to adisintegration or dry defibration directly from the bales. One suchproposal involves the use of a plurality of parallel saw or tearingtooth chains which act on the bales from one side. The resultsheretofore achieved are not satisfying from the quality point of view,and furthermore it has been found that the power demand is too high;also, such proposed machines with saw or tearing tooth chains arecomparatively susceptible to operational disturbances.

The object of the present invention is to provide a machine for thedisintegration of cellulose pulp sheets wherein the above discussedlimitations and drawbacks are eliminated. To this end, apparatusaccording to the invention comprises an essentially vertical magazine toreceivepulp sheet bales with the sheets preferably lying horizontally,said magazine having a bottom consisting of a bed of slightly spaced,mutually parallel tearing tooth rods which are longitudinally relativelymovable to one another and may include two groups which are alternatelymovable in opposite directions.

The invention will be disclosed in more detail below with reference hadto the accompanying drawings, wherein:

FIG. 1 is a perspective view, partly in section, of apparatus accordingto the present invention;

FIG. 2 is a perspective view of a complete disintegrating machinery,including the apparatus of FIG. 1.

The apparatus of FIG. 1 comprises a frame which supports an at leastessentially vertical magazine 11 which may be open on one side to permitinspection of the supply of pulp sheets therein. At least the upper partof the magazine has two flaps 13,14 which may be swung sidewardly bymeans of hydraulic or pneumatic cylinders 12 to permit loading ofcellulose pulp sheet bales from one side, e.g. by means of a fork lifttruck. The pile of pulp sheets has been denoted 15.

The bottom of the magazine on which the pile of pulp sheet rests,comprises a bed of slightly spaced tearing tooth bars 16. In the exampleshown, the bars 16 are divided into two groups, with the bars of eachgroup disposed alternately with the bars of the other group and with thebars 16 of both groups longitudinally movable to-and-fro, alternately inopposite directions. The movement is in this case accomplished by meansof a crank and lever mechanism, generally denoted 17, which over asuitable transmission 18 is driven by means of an electric motor 19. Inas much as a plurality of different drive mechanisms may be used todrive the toothed rods 16 to-and-fro through a suitable stroke which maybe variable, if desired, and with a suitable frequency, it has beendeemed unnecessary to disclose such mechanisms in more details. The rods16 of each group are preferably rigidly interconnected and therespective groups are guided on guide rails 20 over rollers 21,22. Ateach end of the magazine there are provided stripping plates 23,24 whichhave teeth or protrusions extending down between the rods 16. Suchplates with protrusions prevent the pulp from passing out laterally forwhich reason the pulp falls down a hopper 25 or the like to a conveyor(not shown in FIG. 1) or directly to a mill or the like for a continueddisintegration.

The design of the teeth of the rods 16 and the mutual spacing betweensuch rods as well as the stroke and frequency thereof may be varied asnecessary. For certain applications, it would also be possible toarrange only some of the rods movable whereas the others may be arrangedstationary.

It should be mentioned that the pulp sheets are not drydefibratedentirely in the machine in FIG. 1 so it may be used directly as fluff indiapers or similar absorbant pads, for example, moreover, the machine inFIG. 1 should preferably be followed by some other machine, such as ahammer mill, for instance, which brings about the final dry defibration.However, it has been found that such a subsequent machine will have sucha great capacity and gives a product of such a high quality that the useof a machine as shown in FIG. 1 in a precedent step is more than welljustified. i

The probably most surprising fact with the machine according to theinvention is that the capacity thereof and the outer appearance of thepulp pieces torn off from the sheets are remarkably uninfluenced by theheight of the sheet pile 15 in the magazine. Of course, this fact isvery important for the function of the subsequent machine or mill sothat this machine may give off an entirely uniform product, irrespectiveof whether or not the preceding machine according to the invention workswith a full or nearly emptied magazine.

FIG. 2 shows a machine for drydefibration of cellulose pulp to be usedas fluff" or absorbent filler in diapers, sanitary pads and the like.This machinery comprises a disintegrator, generally denoted 50, which ispreferably of the kind as shown in FIG. 1. The pulp sheet pieces are feddown on to a conveyor 51, driven by a drive mechanism 52. The conveyor51 brings the pulp sheet pieces upwardly to the upper end of a mill 53,from which the still further disintegrated pulp sheet pieces are broughtupwardly by means of a second conveyor 54, and areplaced on a furtheroverhead conveyor 55 which may run horizontally beneath the ceiling of adiaper plant, for instance.

A guide 56 diverts the pieces off from the overhead conveyor 55 into ahopper 57; preferably the plant has one such hopper 57 for eachmanufacturing line in the plant, in which case the guide 56 may takeonly a part of the mass off from the overhead conveyor 55 for eachhopper.

The hopper 57 stores a supply 58 of disintegrated pulp which may beready for use or nearly ready for use. The bottom of the hopper isconstituted by the upper flight of an endless belt 59, driven in thedirection indicated by arrow A, and one side wall of the hopper isconstituted by the inner flight of another endless belt 60, driven inthe direction as indicated by arrows B. These conveyors or belts 59 and60, which have serrated surfaces or surfaces with protrusions, ridges orthe like, serve to bring about a mixing action in the pulp supply 58 tomake it uniform in consistency. A brush roller 61 serves to take out thedisintegrated pulp from a slot between belts 59 and 60.

What we claim is:

l. A machine for disintegration and drydefibration of cellulose pulpsheets, comprising an essentially vertical magazine to receive pulpsheet bales with the sheets lying horizontally, said magazine having abottom consisting of a bed of slightly spaced, mutually parallel tearingtooth rods, of which at least some are longitudinally movableto-and-fro, said tearing tooth rods being divided into two groups whichare alternately movable in opposite directions.

2. A machine as claimed in claim 1, wherein the tearing tooth rods ofeach group are mutually interconnected and in that the two groups arealternately movable to-and-fro in opposite directions.

3. A machine as claimed in claim 2, wherein the two groups of tearingtooth rods are movable to-and-fro by means of the same drive mechanism.

4. A machine as claimed in claim 1, further including stripper platesdisposed transversely of said rods at the ends of the tearing tooth rodbed.

5. A machine as claimed in claim 3 wherein said drive mechanism includesa crank and lever means having adjustable stroke and frequency.

6. A machine for disintegration and drydefibration of cellulose pulpsheets, comprising an essentially vertical magazine to receive pulpsheet bales, said magazine having a bottom consisting of a bed ofslightly spaced, mutually parallel tearing tooth rods longitudinallyrelatively movable to one another.

7. A machine as claimed in claim 6, wherein the tearing tooth rods aredivided alternately into two groups.

8. A machine as claimed in claim 7 further including stripper plateshaving protrusions extending down between the tearing tooth rodsdisposed transversely of said rods at the ends of the tearing tooth rodbed.

1. A machine for disintegration and drydefibration of cellulose pulpsheets, comprising an essentially vertical magazine to receive pulpsheet bales with the sheets lying horizontally, said magazine having abottom consisting of a bed of slightly spaced, mutually parallel tearingtooth rods, of which at least some are longitudinally movableto-and-fro, said tearing tooth rods being divided into two groups whichare alternately movable in opposite directions.
 2. A machine as claimedin claim 1, wherein the tearing tooth rods of each group are mutuallyinterconnected and in that the two groups are alternately movableto-and-fro in opposite directions.
 3. A machine as claimed in claim 2,wherein the two groups of tearing tooth rods are movable to-and-fro bymeans of the same drive mechanism.
 4. A machine as claimed in claim 1,further including stripper plates disposed transversely of said rods atthe ends of the tearing tooth rod bed.
 5. A machine as claimed in claim3 wherein said drive mechanism includes a crank and lever means havingadjustable stroke and frequency.
 6. A machine for disintegration anddrydefibration of cellulose pulp sheets, comprising an essentiallyvertical magazine to receive pulp sheet bales, said magazine having abottom consisting of a bed of slightly spaced, mutually parallel tearingtooth rods longitudinally relatively movable to one another.
 7. Amachine as claimed in claim 6, wherein the tearing tooth rods aredivided alternately into two groups.
 8. A machine as claimed in claim 7further including stripper plates having protrusions extending downbetween the tearing tooth rods disposed transversely of said rods at theends of the tearing tooth rod bed.